The relationship between alexithymia and Nyght Eating Syndrome

Introduction NES is characterized by daytime anorexia, sleep difficulties with nocturnal food intake, resulting in obesity (Stunkard et al. Am J of Med. 1955; 19 78-86). Alexithymia refers to the impairment in recognizing and describing feelings. The impairment in distinguishing emotions from body sensations may lead patients to confuse emotional arousal with physical hunger (Sifneos et al. Mod. trends psychosom. med. 1976; 3 430-439). This mechanism could lead to nocturnal food intake. Alexithymia was firstly described in BED and was related to BED severity. Objectives To our knowledge no studies have investigated the relationship between alexithymia and NES. The aim of the present study was to assess alexithymia in patients with NES, to improve surgical and nutritional outcomes. Methods 110 patients with clinical diagnosis of NES admitted to the Eating Disorder Unit, between 2013 and 2022 underwent psychiatric assessment for bariatric surgery. Clinical assessment consisted of clinical interview and the following psychometric rating scales: 20-item Toronto Alexithymia Scale; Eating Disorder Inventory 2, specifically the Interoceptive Awareness subscale; Barratt Impulsiveness Scale; Binge Eating Scale. Results The mean BES score was 24.14(SD 8.23), computed on 107 patients, of which 16 (14.5%) had no or minimal binge eating problems and 91 (82.7%) had moderate-severe binge eating problems. The mean TAS total score was 55.11(12.92), computed on 103 patients. 42 patients had a TAS-20 total score ≤50 and were categorized as non-alexithymic, and 61 had a TAS-20 total score >50 and were categorized as alexithymic. Simple linear regression was used to test if TAS-20 total score significantly predicted EDI-IA in the whole sample (97 patients). The overall regression was statistically significant (R2=0.27, F(1,96)=35.46, p< .001) and TAS total score significantly predicted EDI-IA score (β=0.519, p<.001). In the alexithymic group, the regression was statistically significant (R2=0.305, F(1,57)=25.07, p< .001) and TAS total score significantly predicted EDI-IA score (β=0.553, p<.001). Whole sample Alexithymic Non-alexithymic p Female (%) 79(71.8)N=110 48(64.9)N=62 26(35.1)N=42 .087 Age mean(SD) 36.41(12.6)N=110 34.65(12.7)N=62 38.48(11.31)N=42 .11 BMI mean(SD) 44.05(7.61)N=106 43.97(7.9)N=60 43.82(7.38)N=40 .92 TAS mean(SD) 55.11(12.92)N=103 64.05(7.06)N=61 42.12(7.13)N=42 <.001* BIS mean(SD) 67.58(10.35)N=98 70.07(9.93)N=59 63.26 (9.85)N=35 .002* BES mean(SD) 24.14(8.23)N=107 25.7(6.89)N=62 21(9.25)N=40 .004* EDI-IA mean(SD) 8.95(6.44)N=103 10.82(7)N=60 6.05(4.44)N=39 .000** significant difference between alexithymic and non-alexithymic groups according to independent sample t-test. Image: Image 2: Conclusions In patients with NES, alexithymia significantly predicts poor interoceptive awareness, thus explaining excessive nocturnal food intake. Disclosure of Interest None Declared

Introduction: NES is characterized by daytime anorexia, sleep difficulties with nocturnal food intake, resulting in obesity (Stunkard et al. Am J of Med. 1955;19 78-86). Alexithymia refers to the impairment in recognizing and describing feelings. The impairment in distinguishing emotions from body sensations may lead patients to confuse emotional arousal with physical hunger (Sifneos et al. Mod. trends psychosom. med. 1976;3 430-439). This mechanism could lead to nocturnal food intake. Alexithymia was firstly described in BED and was related to BED severity. Objectives: To our knowledge no studies have investigated the relationship between alexithymia and NES. The aim of the present study was to assess alexithymia in patients with NES, to improve surgical and nutritional outcomes. Methods: 110 patients with clinical diagnosis of NES admitted to the Eating Disorder Unit, between 2013 and 2022 underwent psychiatric assessment for bariatric surgery. Clinical assessment consisted of clinical interview and the following psychometric rating scales: 20-item Toronto Alexithymia Scale; Eating Disorder Inventory 2, specifically the Interoceptive Awareness subscale; Barratt Impulsiveness Scale; Binge Eating Scale. Results: The mean BES score was 24.14(SD 8.23), computed on 107 patients, of which 16 (14.5%) had no or minimal binge eating problems and 91 (82.7%) had moderate-severe binge eating problems. The mean TAS total score was 55.11(12.92), computed on 103 patients. 42 patients had a TAS-20 total score ≤50 and were categorized as non-alexithymic, and 61 had a TAS-20 total score >50 and were categorized as alexithymic. Simple linear regression was used to test if TAS-20 total score significantly predicted EDI-IA in the whole sample (97 patients). The overall regression was statistically significant (R 2 =0.27, F(1,96)=35.46, p< .001) and TAS total score significantly predicted EDI-IA score (β=0.519, p<.001). In the alexithymic group, the regression was statistically significant (R 2 =0.305, F(1,57)=25.07, p< .001) and TAS total score significantly predicted EDI-IA score (β=0.553, p<.001).

Image:
Whole sample Alexithymic .000* *significant difference between alexithymic and non-alexithymic groups according to independent sample t-test.

Image 2:
Conclusions: In patients with NES, alexithymia significantly predicts poor interoceptive awareness, thus explaining excessive nocturnal food intake.

EPP0608
Mirror exposure therapies: Effect of the distance to the mirror on the attentional pattern in a Virtual Reality immersive environment Introduction: Mirror exposure therapies (MET) have been proposed to reduce symptomatology in patients with Anorexia Nervosa. However, most MET protocols or related studies do not specify the patients' distance to the mirror, or when they do so, such a distance may differ significantly (from 0,5 to 3 meters). Such modifications of mirror positioning could imply variations in patients' fixation patterns on different body parts (i.e., attentional bias between weight-related and non-weight related body parts), since previous studies shown that dissociated neural systems (either in left or right cerebral hemispheres) are involved in the attentional patterns and scanning strategies depending on the distance (i.e., in near and far space). Furthermore, as the body-related attentional bias (AB) has been shown to be a part of the maintenance mechanism of AN symptomatology, any modification of attentional patterns due to mirror's distance variations may influence the efficacy of MET.
Objectives: This study aims to use Virtual Reality (VR) and Eye-Tracking (ET) technologies to precisely analyse the effect of the distance to the mirror on the attentional patterns.
Methods: 137 female college students were immersed in a VR environment in which they could look in the mirror at their respective avatars created from the measurements and photos of their real bodies. The mirror was positioned at 3.30m in front of the participants in "group 1" (n 1 = 54), and at 1.54m in front of the participants in "group 2" (n 2 = 83). Eye-Tracking feature and OGAMA software (Freie Universität, Berlin, Germany) were used to record and process the visual attentional pattern of each participant, during a 30-second free viewing task at her avatar. Complete Fixation Time (CFT) was assessed as the fixation time difference between weight-and non-weight-related body parts, defined from the weight scale of the PASTAS questionnaire. Independent Sample t-Test was conducted to analyse CFT mean difference between both groups. Results: Independent Samples t-Test shows statistically significant CFT mean difference (F (1, 135) = 1.571, p < 0.001, 95% IC [1717; 5581]) between both groups. While fixation pattern of the group positioned further to the mirror (group 1) was more focused on weight-related body parts (CFT mean = 2282ms, SD = 809), the fixation pattern of the group positioned closer to the mirror (group 2) was more focused on non-weight-related body parts (CFT mean = -1367ms, SD = 587).
Conclusions: This study shows new opportunities to use VR and ET technologies to precisely analyse the variations of fixation patterns as a function of mirror position in MET. Such information may contribute to adapt and develop new MET's protocols for AN patients, optimizing the distance to the mirror. It also underscores the importance of specifying the distance to the mirror in METrelated studies to improve replicability.

EPP0609
Serotonin, insulin, leptin and glycolipid metabolic factor's relationship in obesity